As is known in the art, cooling structures used in many applications to transfer heat generated away from a heat source, such as from an integrated circuit. One such cooling structure is a channelized cooling structure wherein a cooling fluid, such as a gas or liquid is directed through the channels around the back side of an integrated circuit. One such arrangement is described in U.S. Pat. No. 8,987,892, issued Mar. 24, 2015, entitled “Method for creating a selective solder seal interface for an integrated circuit cooling system”, inventors Davis et al., assigned to the same assignee as the present patent application. Another type of cooling structure includes a plurality of thermally conductive member having one end thermally coupled to the heat source and the opposite end connected to a heat sink. Both types of cooling structures are also sometime referred to as heat spreaders.
Because of its high thermal conductivity diamond cooling structures have been suggested. One such structure is described in a paper entitled “Microchannel Cooled, High Power GaN-on-Diamond MMIC” by T. Creamer, K. K. Chu, P. C. Chao, B. Schmanski, T. Yurovchak, S. Sweetland, Geoff Campbell and Henry Eppich, published in Lester Eastman Conference on High Performance Devices (LEC), 2014, 978-1-4799-6441-3/14 ©2014 IEEE. As described therein, methods for fabricating via holes and slots in, what appears to be a diamond block using approaches that include drilling and etching processes were being investigated. Thus, such approach would require the time consuming process of first forming a diamond block, and then removal of portions of the diamond; diamond being a relatively expensive material.
Another technique used to provide a diamond cooling structure is Volume 9, Issue 2, 1 Mar. 2000, Pages 201-204 Effective thermal conductivity of a diamond coated heat spreader by K. J Gray.